Tuesday, February 21, 2006

High tunnel heat math ... is it worth it?

The cold over the last weekend got me calculating how much heat I would need for my vinifera to survive a cold snap. Although I'm sure the equation has several more terms than I care to account for, I think I can use a basic equation for a rough estimate.

(Surface AREA in SQFT )*(Temperature difference in F)*1.2 =BTUs of heat needed

The hoop house I intend to use will have an area of about (96*16*PI)+(PI*16*16)=6,534.5 SQFT

Let's try an example:
From the last weekend ... I spent 19 consecutive hours below 3 F The average Temperature over this period was about -8 F or an average temperature difference during this time of about 11 F.

So ..... (6,534.5*11*1.2)=86,255 BTU/hour needed to remain at 3F or higher.
I have two 60,000 BTU forced air kerosene heaters. They should be able to supply a total of 120,000 BTUs per hour. They can last about 12 hours of continuous heating.

So based on this ... I should be able to last a little less than 17 hours. These calculations do not take in account any thermal inertial due to heat retained in the ground or any additional insulation ... which I intend to use. I may have to get a couple of backup heaters ... or refuel more often.

Next, I have to build my computerized controllers .... luckily I have quite a bit of experience with this part. The entire computer controlled heating system should cost about $400 to build(including heaters). Fuel should cost about $4/hr. Even in a cold year, cheap insurance to keep the vines alive. This year it would have cost me about $100 bucks in fuel costs (worse case) to allow my 75 vinifera vines to survive the winter.

Extending the costs over 10 years .... assume on average 100 hours of heat per year over 10 years:
high tunnel=$4000 --- one time cost
heat=$4000 ---- ~$400 per year
Other misc =$500 --- sensors, computer controller ... tarps etc.
Assume 20 lbs/vine/year

So this system will add $0.56 per pound of grapes. Even if you go best/worst case ... I think you can go plus or minus a .25 per pound i.e. $.31 - $.81/lb . .... note vinifera shipped in from the west coast will cost any where from $0.65 to as much as $1.50 per pound (in small quantities) when shipping is included, so then this begins to look competitive. And hey.... they were grown in Wisconsin! And this does not take into account the reduced risks due to Frosts, Winter kill, reduced pests, and the costs associated with them. This is all theory so far ... we will see how reality plays out ... it may be far more harsh than I anticipate, but many of the numbers and costs I used I hope to beat.

Sunday, February 19, 2006

A bit chilly (-17 F in the shade)

A late winter cold snap hit the vineyard this weekend. Friday night the temperature dropped to -17 F. It's the coldest weather we have had since the vineyard was planted in 2003. Last night we dropped down to -7 F. Luckily we had about 10 inches of fresh snow added to the 8 inches already on the ground. I am concerned that the recent mild weather (i.e. all of January, and the beginning of February) may have hurt the hardiness of some of the vines. I think the Vinifera under the tarps were fine. Thankfully the vineyard didn't get as cold as my backyard here in Madison, where I recorded -21F.

Monday, February 13, 2006

What's Under there??

I was up at the vineyard this past weekend. A good 8 inches of snow should keep the ground well insulated for the upcoming cold.

I noticed a lot of activity around the vinifera under the tarp. I saw a lot of tracks ... I think they were either coyote or fox ....

I also see some digging.... I wonder if the coyote (or fox) could here rodents under the tarp?

If so I hope the little critters living under there aren't feasting on the vines!

Sunday, February 05, 2006

Day 2 at the Wine and Grape Conference

Yesterday, was another great day at the conference! The organizers did a spectacular job running this conference.

The day started with a real nice breakfast .... fruit, eggs, sausage bacon, crepes ... you name it, much better than the typical continental breakfast spreads. But enough about that ..... Lets get to the wine and grape talks.

The morning started out with a keynote about the Winegrape industry in Iowa. This was followed by parallel sessions dealing with wine or grapes.

Luckily, two folks I knew and were attending the conference, Randy Harrison and Norm Stilson, attended some of the talks that I missed, so I will have to tap them for more info on the talks I did not attend. (Randy is a amateur winemaker and attended some of the winemaking talks. Norm is a grower and also makes wine, so he was splitting his time between the parallel tracks, as was I.)

So here is the quick summary:

Iowa experience (Mike White)
13 Iowa wineries in 1999 ->52+ wineries by Feb 2006
31 acres grapes growing in Iowa in 1999 -> 600+ in 2005
imported a lot of expertise

Evaluating Cold Climate Cultivars (Dr. Paul Domoto)
Late Frosts have huge impacts on many of the cultivars. And organic is a challenge in the Midwest. Site selection has huge impacts.

Wine Faults (Todd Steiner)
Don't skimp on those sulfites!

Lunch (quite the spread again!)

Wine Makers Forum(various)
Sweeter wine sells ... Iowa and Minnesota wines aren't cheap!

Working together as a State Grape and Wine industry (Donniella Winchell)
With good outreach, networking and smart promotion a grape and wine industry can reap huge benifits.

Dinner and a tribute to Bob Wollersheim
A great dinner and a heart tugging tribute to Bob Wollersheim

If I haven't lost you yet ... here are the details. (note this may or may not be the highlights, just my impressions.)

Iowa experience
This was presented by Mike White (a very entertaining guy by the way) from Iowa State University Extension.
What they have done in Iowa
since 1999 is impressive. Going from ~30 acres of vines to over 600 now. They had 13 wineries in 1999 and 52+ now. This was no accident. It helped that Iowa invested in the industry .... a wine and grape development council was appointed, the Universities hired researchers, extension specialists, and more.

They were also beneficiaries of some unique native winery laws like Native Wineries being exempt from some wine taxes, liberal licensing to sell Native winery wines at businesses that are not typical wine outlets (like flower shops, gift shops, etc) cheap/liberal licensing to allow wine sales by the glass at festivals and events.

This talk made me wonder why ..... WHY ... isn't Wisconsin doing some of the same things?

Evaluating Cold Climate Cultivars
This was presented by Dr. Paul Domoto. Dr. Domoto is a horticulture professor at the Iowa state University. This talk was somewhat Iowa centric, but in some ways was more relevant to my climate than many of the Minnesota oriented talks.
Dr. Domoto talked about two sites growing the same grapes. One site was significantly more frost prone than the other. Three management systems were also evaluated. They were:
-IPM/Best Practices
-Organic Approved

In many cases the difference in these approaches were by far insignificant when it came to site factors ... such as frosts and cold injury. However, in general the organic suffered as one may expect.
Some general Notes:
All of the cultivars varied significantly. While there was a variation between cultivars, there was a huge variation between the sites. When there were late spring frosts, it had a huge impact. The cultivars with late bud beak had virtually no damage.
Winter low temperatures between the two sites varied by about 8 degrees -11F at one site -19F at the other. Huge difference were seen due to bud damage from the colder temperatures.
Additional sites and cultivars have been planted and additional information will be coming from those.
A lot of info was presented in this talk ... I don't think I even hit all of the highlights.

Wine Faults
This was a talk I really looked forward to. It was presented by Todd Steiner from the University of Ohio. We did not get a handout on this, so I have limited notes.
We evaluated 10 wines, 5 red, and 5 white. One red was a control with no faults and one white was a control with no faults. We first tried the whites:
I was easily able to identify the flaw in both #2 and #3 (since I have had wines that suffered each)
1. White Wine control
2. Oxidized white. Brownish in color sweet nutty sherry aroma and taste .... due to too much oxygen . Too much head space, too much splashing when racking. This is the least offensive to me, since I like sherry. But this is a recognized fault.
3. VA problem i.e. volatile acidity problem i.e. acetic acid i.e. VINEGAR. Distinct vinegar smell. Due to poor sanitation, or insufficient sulfites, too much oxygen or head space.
4. lactic acid spoilage. This one smelled like sauerkraut. May sometimes have a ropey filaments in it, but is less common. Due to insufficient SO2(sulfites). Typically due to a natural malolactic culture.
5. Protein haze. We only got to see this one.

Now the reds.
I recognized 2 out of the 4 flaws. Only once did I have a wine suffer from one (#9).

6. Red control
7. High alcohol and fusel alcohols. I thought this smelled a bit like lighter fluid, rubber (and slightly like rotting flesh!) it had a hot taste. This is often due to certain yeast strains and or high fermentation temperatures.
8. Brett ... I have read about this, but did not know what it smelled like. It smells like a first aid kit or band aids. Brett is caused by a bacteria, so sulfites would help, but it is anaerobic so air is less of a factor.
Sometimes found in Bordeaux wines (intentionally?)
9. Film yeast . Wine flowers, ethel acetate. Smelled like fruity nail polish remover. Prevented with adequate sulfites and topping up.
10. Geranium smell due to adding sorbate to a malolactic fermented wine. I have noted this in a couple of wines I've tried ... never my own, since I haven't added sorbate to very many. This example was a commercial wine, and it had an overpowering geranium smell! Simple solution; keep sulfites up so malolactic does not start, or don't add sorbate to a malolactic fermented wine .... be careful with blending .... a malo fermented wine blended with a sorbated wine is just as bad.

Winemaker Round table
I won't go into too much detail here, but this was a fascinating one. We try 10+ different wines with the winemakers of those wines explaining in detail the chemistry and methods for making the wines. Great insights are gained from this. I was shocked at some of the prices that they sell these wines for. I think $12 was the cheapest. Most were between $15 and $20. When we were trying the sweeter wines, one of the wine makers noted that it wasn't his favorite, but by far the sweeter wines were the ones that sell.

Working together as a State Grape and Wine industry
This was the final talk and the keynote. Donniella Winchell gave this presentation .... she is the Executive Director of the Ohio Wine producers association. There was too much information to even touch a little on what was presented in this talk. The bottom line was you really have to get involved and network at every level .... from legislatures to tourism boards to news media. You really need to promote. Great info.

Dinner and tribute to Bob Wollersheim
The conference concluded with a dinner and tribute to Bob Wollersheim. The dinner was served with several bottles of wine from some of the attendee wine makers.
At the end of the dinner
Philippe Coquard, who is the son-in-law of Bob Wollersheim and winemaker at the Wollersheim winery, showed a movie that was wonderful picture history of the Wollersheim winery that Bob Wollersheim himself made in 2002. Bob was also posthumously awarded the Elmer Swenson Achievement Award, Philippe and JoAnn Wollersheim accepted the award on Bob's behalf.

Friday, February 03, 2006

Minnesota Grape Growers Association Cold climate Grape and Wine Conference …. And a break in the “heat” wave.

(NOTE if you are looking for Minnesota Grape Grower Association here is the link

http://www.mngrapes.org/ Not sure why google is directing everyone to this page instead of that one? But look around if you like.)

Today is the first day of the MGGA Cold Climate Grape and Wine Conference. As last year, it has already proven to be well worth it.

Okay … the weather on the drive in wasn’t the greatest, but from what I heard from others, it sounded like I beat the worst of it. I left Madison about 6:45 am this morning and arrived in Rochester, MN around 10:00 am the drive was fine up until the last 30 miles, when rain started freezing on my car and road. Luckily traffic was light and I made it to the Kahler Grand Hotel safe and sound. Looks like our 40+ day streak of 30F or higher is over.

This afternoon’s talks were about:

-Grape Diseases

-Grape Pests (primarily of the bug variety)

-Grape Growing Keys to success

-Vineyard Fertilization

-Vineyard Economics

So far all of this year's presentations were presented by “academics.” Last year it was nice to get the mix real life grower experiences along with the academics, but I really enjoyed this years more academic approach.

First a quick summary of each talk, then a little more info:

Grape Diseases:

Black Rot and Downy Mildew 2 top grape diseases in Illinois. Moisture in general bad. Get a handle on them early.

Grape Pests

Fairly easy to deal with it… the longer and more common grapes are grown in the Midwest, the more there will be.

Grape Growing Keys to success

Location, Location, Location …. Oh and use good vineyard practices

Vineyard Fertilization

Preparation, preparation, preparation … i.e. get it right before you plant

Vineyard Economics

So you want to start a vineyard … you must be crazy

The WINE reception

Drink wine, talk, drink some more wine, talk some more, drink more wine

Okay … now a little more detail on what I remember the most from each talk.

Grape Diseases (the longer version)

Presented by Dr. Mohammad Babadoost

This was a great talk. I gained a greater understanding of how to deal with some of the disease issues that I have had in my vineyard. Specifically, I learned that I have spots of Anthracnose scattered throughout my vineyard. This was something that I noticed, but despite my research I hadn’t been able to identify it … seems easy to deal with. Liquid lime sulfur should take care of this … should be sprayed while vines are dormant … I will probably do this in March.

Several literature resources were also provided, and I will probably try to get some of those.

And finally some suggest spray schedules were provided that I may draw upon. Over all very educational. He mentioned that Black Rot and Downey mildew were the two biggest diseases in Illinois, but it has clearly been a different story at my vineyard.

Grape Pests

Dr. Bill Shoemaker

Very interesting, but luckily most or all of the pests that were discussed have not been an issue in my vineyard … that is except for Deer. Rose chafers were not even mentioned …. Am I the only one that these buggers attacked!!!?

He also mentioned that we are still learning about which pests will be issues in the future. As more grapes are planted, and the longer they are in this area, new pests will emerge as problems.

Grape Growing Keys to success

Eli Bergmeier

Another great talk, but not enough time to cover all that he had…. He could have easily gone another hour, and not covered all of his topics.

He mentioned that two of the biggest reasons for Vineyard Failure are Site selection and weeds …. Yes WEEDS ! He showed an example of how a site with poor cold air drainage had a frost 2-3 weeks earlier than another nearby location with good cold air drainage, and 3 late spring frosts versus the location with good drainage, that only had one!

He also touched on the wetness of the location … not much new here for me.

He also talked a bit about planting …. He used an auger similar to me, but I learned that something called glazing can occur. … This is when the sides of the auger hole are wet and compacted, and create a clay pot situation … I don’t think this has been an issue for me, since my soil has a good organic matter content (~2%) …i.e. not too high, and is relatively loamy.

Time was running short, and I wish he would have spent more time on trellising, but I have enough info from the handouts so I can study them.

Vineyard Fertilization:

Dr. Paul Domoto

If I had to choose a favorite section, it wouldn’t be easy, but this would be it. I liked this talk so much, because this was information I was desperate for. I had my petiole and soil and analysis done this year, but I felt like it was not interpreted well enough, and the significance of certain things were not clear to me.

Dr. Domoto broke down the ideal values for the types of cultivars grown in this climate. Bottom line …. My Potasium is way too low, but I knew this. That is why I added the soil amendment this fall. And by PH is too high. 6.0-6.5 is ideal, mine is about 7.0.

Of course I should have made my adjustments prior to planting … which I did with my latest vines, but the little additional info I have now, would have been a big help.

Here are my numbers compared to the ideal

Petiole Nutrient


My Vineyard


.9 - 1.3 %



.16 - .29 %



1.5-2.5 %



1.2-1.8 %



.26-.45 %



>.1 %



30 - 50 ppm



25-50 ppm



31-150 ppm



31-50 ppm



5 - 15 ppm


Soil Sample

Soil ph

6 - 6.5



2 - 3 %


Vineyard Economics

Dr. Bill Shoemaker

The last talk also by Dr. Shoemaker, was kind of a reality check …. Basically… be prepared to not make any money for a while. You really need to plan and treat this vineyard like a business …. Maybe obvious, but you really need a business plan. I wrote one up a while ago, but I realize now, that I need to add much more detail. I asked the guy next to me (Kent), who hasn’t started his vineyard yet, but is in the planning stages … “ So did he scare you?” he said “nope” …. I thought …. I already made most of the mistakes he mentioned, and so hey … bring it on!.

The Reception

The talks were great, but the reception Friday evening was another thing to look forward to. This gave everyone a great opportunity to mingle, learn, and sample many different wines.

I talked a bit with Mark Hart from Bayfield, WI … he’s a grape breeder on the shore of lake Superior. I asked him a bunch of questions about grape hardiness as it relates to warm and cold spells. He said the biggest risk are big fluctuations … more so than the extremes … well not too extreme. He said that when we go from warm (50+) to very cold –10F over a short period of time, that is more damaging than a slow progression from one to the other. Good to know.

Then there was the wine …. I would have to say that some of the amatures matched or easily surpassed some of the commercial wineries. Tasted some very interesting blush style wines, some very good whites, and a lot of good reds … probably tried 20 or 30 total …. Definitely had to dump and pace myself. Tasted a very good Frontenac, Cabernet Sauvignon, Zinfindale blend. Couple of good Frontenac … some not as good Foch. And a couple of amature wines that were better than some of the big guys.

More tomorrow.